Abstract:
[Object] To provide a pneumatic tire 22 that allows a low fitting pressure to be achieved without impairing a tightening force.[Solution] The tire 22 includes a pair of beads 30 and a carcass 32 extending on and between both beads 30. Each bead 30 includes a core 48. The core 48 includes: a main body 56 including a cord 60 extending in a circumferential direction; and a stretchable portion 58 formed from a crosslinked rubber. The stretchable portion 58 is located inward of the main body 56 in an axial direction. The stretchable portion 58 has a size with which at least one cross-section of the cord 60 can be included therein in a cross-section of the bead 30. Preferably, in the tire 22, the main body 56 includes a hard unit and a soft unit. The soft unit is located outward of the hard unit in a radial direction. A hard cord of the hard unit stretches more easily than a soft cord of the soft unit.
Abstract:
A steel cord is configured so that, when the steel cord is used as a tensile cord for an elastic crawler, a center-core dislocation and the early breakage of the wires of a core are prevented. A steel cord comprises: a core which comprises a single core strand, and a sheath which is formed by twisting together six sheath strands arranged around the core. The core strand has a layer-twisted structure comprising: a center-core portion which is formed by twisting three core wires together; and an external layer portion which is formed by twisting together eight to nine core wires arranged around the center-core portion. The sheath strands each have either a bundle twisted structure which is formed by twisting twelve to nineteen sheath wires or a multi-layer twisted structure which is formed by twisting twelve to nineteen sheath wires in layers. The diameter (dc) of the core wires is greater than the diameter (ds) of the sheath wi res. The average gap (Gc) between the core wi res of the external layer portion is 0.015 mm or greater, and the average gap (Gs) between the sheath strands is 0.1 mm or greater.
Abstract:
To provide a pneumatic tire wherein the lightweight properties of a tire is secured while improving the plunger energy and BES resistance thereof, which is particularly suitable for tires for a large passenger car or extra load tires.A pneumatic tire comprising a carcass 1 as a skeleton, and at least two belt layers 2a, 2b each formed by rubberizing a plurality of steel cords arranged obliquely with respect to the tire circumferential direction on the outside in the tire radial direction of the crown portion of the carcass is provided. The steel cord is composed of two or more core wires and five to seven sheath wires twisted together around the core wires; the interval between adjacent steel cords in the belt layer is more than 1.0 mm and not more than 1.50 mm; and the gauge of the belt layer is not less than 1.20 mm and not more than 1.60 mm.
Abstract:
In order to provide a double rustproof PC strand with superior durability and semi-permanent rustproof performance, a core wire and surrounding wires are formed of wires subjected to a wire drawing treatment and a plating treatment and formed with a plated layer, and a rustproof treatment is applied by forming a synthetic resin coat on an outer peripheral surface thereof. In order to uniformize and regulate the twisting pitch, the core wire and the surrounding wires are adjusted under the conditions of (A) Diameter of CORE: 4.42±0.05 mm, Diameter of Surrounding wire: 4.25±0.05 mm, (B) Diameter of CORE: 5.22±0.05 mm, Diameter of Surrounding wire: 5.06±0.05 mm, or (C) Diameter of CORE: 5.40±0.05 mm, Diameter of Surrounding wire: 5.25±0.05 mm, and then twisted, and the tensile strength is 1850 N/mm2 or higher.
Abstract translation:为了提供具有优异的耐久性和半永久性防锈性能的双重防锈PC绞线,芯线和周围的线由经过拉丝处理和电镀处理的电线形成,并且形成有镀层,并且防锈处理 通过在其外周面上形成合成树脂涂层来施加。 为了使捻距均匀化和调节,在(A)直径CORE为4.42±0.05mm,周围线直径为4.25±0.05mm的条件下,对芯线和周围线进行调整,(B)直径 核心:5.22±0.05mm,周围线直径:5.06±0.05mm,或(C)直径CORE:5.40±0.05mm,周围线直径:5.25±0.05mm,扭转,拉伸强度为1850 N / mm2以上。
Abstract:
To provide a pneumatic tire wherein the lightweight properties of a tire is secured while improving the plunger energy and BES resistance thereof, which is particularly suitable for tires for a large passenger car or extra load tires.A pneumatic tire comprising a carcass 1 as a skeleton, and at least two belt layers 2a, 2b each formed by rubberizing a plurality of steel cords arranged obliquely with respect to the tire circumferential direction on the outside in the tire radial direction of the crown portion of the carcass is provided. The steel cord is composed of two or more core wires and five to seven sheath wires twisted together around the core wires; the interval between adjacent steel cords in the belt layer is more than 1.0 mm and not more than 1.50 mm; and the gauge of the belt layer is not less than 1.20 mm and not more than 1.60 mm.
Abstract:
A device and method for manufacturing a metal cord with three concentric layers, rubberized in situ, of M+N+P construction, wherein the method comprises the following steps which are performed in line: an assembling step by twisting N wires around a first layer to form, at a point named the “assembling point”, an intermediate cord named a “core strand” of M+N construction; downstream of the assembling point, a sheathing step in which the M+N core strand is sheathed with a rubber composition named “filling rubber” in the uncrosslinked state, an assembling step in which P wires of the first layer are twisted around the core strand thus sheathed, and a final twist-balancing step.
Abstract:
A tire having a radial carcass reinforcement, including at least one layer of reinforcing elements, said tire comprising a crown reinforcement, which is itself covered radially with a tread, said tread being joined to two beads via two sidewalls. The reinforcing elements of at least one layer of the carcass reinforcement are hybrid cords having at least two layers. At least one strand of the core of each of said hybrid cords includes textile multifilament yarns. The strands of the intermediate and/or outer layers are metallic, and at least one inner layer is sheathed with a layer including a polymeric composition such as a crosslinkable or crosslinked rubber composition.
Abstract:
A steel cord having a 1×2 construction formed by twisting two wire strands together is used as a reinforcing layer of a pneumatic tire. The steel cord has a carbon content of from 0.60 to 0.75%, a strength in the tire of from 2,900 to 3,500 MPa, and a twisting angle of from 1.5 to 3.0°. Therefore, productivity can be enhanced while fatigue resistance of the steel cord used in the reinforcing layer is maintained. Additionally, fatigue resistance of the steel cord is further enhanced due to the average value of the forming factor of the steel cord of this tire being set to from 95 to 105% and the standard deviation σ being set to from 5 to 20%. As a result, tire durability can be enhanced.
Abstract:
A steel cord for reinforcing rubber article having a 1×n structure composed of a plurality of steel filaments stranded in the same direction at the same stranding pitch, the number of the steel filaments being 6 to 12 and the diameter of the steel filaments being 0.08 to 0.21 mm. In the pneumatic radial tire having a carcass, as a framework, extending toroidally between a pair of bead parts, with a crown part of the carcass being reinforced with a belt layer, the above-described steel cord for reinforcing rubber article is applied to a cord constituting the belt layer.
Abstract:
A pneumatic tire for a passenger car includes a belt layer and a belt cover layer formed by winding a steel cord member in the tire circumference direction on the outer peripheral side of the belt layer. The steel cord member has a structure in which element wires made of steel and having a diameter smaller than 0.18 mm are twisted together to form each strand and the strands are twisted together in the same direction as the direction of twisting of the element wires. The twist pitch on each of the strands is smaller than the twist pitch on the steel cord member, the twist pitch on the strand is 1.0 mm to 2.1 mm, and the twist pitch on the steel cord member is 2.0 mm to 5.25 mm.